Electric furnace operation



June 4, 1935. P. L J MiGUET :1" AL ELECTRIC FURNACE OPERATION Original Filed April 12, 19-33 Patented June 4, 1935 UNITED STATES PATENT OFFICE 2,003,653 ELECTRIC FURNACE OPERATION Paul Louis Joseph Miguet and Marcel Paul Perron, St. Julien de Maurienne, France Continuation of application Serial No. 665,787, April 12, 1933. This application July 16, 1934, Serial No. 735,492. In France April 30, 1932 1 Claim. (Cl. lib-34) This application is a continuation of our apelectrode of which the periphery is alternately plication Serial No. 665,787, filed April 12, 1933. composed of baked and unbaked segmentsas This invention relates to an improved form shown in the figures; the unbaked segments H,

of electrode for electric furnaces, and particuof greater chemical activity, being disposed op- 5 larly to a compound electrode especially adapted posite the portions 9 of the charge free from the 5 for use in connection with the method of operatlenticular masses, and the pre-baked segments ing electric furnaces described in our prior Pat- I2 being disposed opposite the lenticular masses ent No, 1,944,521, issued Jan. 23, 1934. 8 as shown more particularly in Fig. 4.

In the prior patent is described a method of In Figs. 1, 2 and 3, the dotted lines indicate. "operating electric furnaces characterized by the the original contour of the electrodes before use. 10 charging of the materials in alternate vertical The new electrode undergoes a uniform latzones comprising inalternation azone of a conduceral consumption and maintains a perfectly regtive mixture of all of the reducing material and ular contour when used in the presence of km Y only a part of the material to be reduced, and a ticular masses as shown in Fig. 3, and also main-- zone comprising the remainder of the material to tains a slope much closer to the vertical than to 5 be reduced in the form of lenticular masses reguthe natural angle of repose .of the material. larly spaced through the mass of the charge. The unbakcd portion of the new electrode may This method of charging has the advantages of be made of a rammed mass having metallurgical providing a discontinuous lateral spreading of the coke as a base, and for this reason it has the current without endangering the refractory lining additional advantage of a much lower cost than of the furnace. without excessive radiation from the prior electrodes. Even when used with the surface, without premature fusion of the macharges free from lenticular masses, as shown in terial to be reduced, and without being influenced Fig. 2, the wearing of the electrodes is sufficientby the depth of molten product on the hearth 1y regular that they may be advantageously used of the furnace. with such charges, in view of their low cost of 5 However, the operation of this process has manufacture.

shown that the perimeter of the electrode hang- The use of a metallic jacket III is very desirins in c ntact with the reacting mass is subjected able, in order to provide a supporting mold for t0 uneven Wearing nsumpti n which is the ramming of segments of unbaked material ll greater when the whole electrode mass is baked between the segments of pro-baked material I2; in Pl h n wh n the perimeter is entirely comthe central filling I3 is preferably rammed in at posed of pre-baked elemen This unevenness the same time. Anyof the known means for join- 'consists of furrows excavated in the electrodes ing and suspending the pre-baked elements may opposite the lenticular masses by the oxidizing be utilized.

'5 action of the reducible materials of which they We claim:

are composed. The improvement in the operation of electric This unevenness, more or less accentuated acfurnaces h n th at l are charged in oordlne es the periphery of h e trode is pr alternate vertical zones comprising in alternation baked r t. resu i in cient support oppoa zone of a conductive mixture of all of the re-.

0 site the furrows for the material being treated. ducing material and only a part or the material 40 causing falling-in of th ch emulsifleetlon to be reduced, and a zone comprising the --reby the excessive production of carbon monoxide, mainder of the material to be reduced in the chilling, and even reversion of the production alform of lenticular regularly spaced rea obtolnedthrough the mass of the charge which comprises a T invention will be n ifl v described supplying current to the charge through elecwith reference to the accompanying drawing in trodes r hi h th periphery is alternately comwmch: posed of prebaked and unbaked segments. the unl' 1 is a v rtic l s on. an Figs. 2 and 3 baked segments being disposed opposite the porare hcris ntal le lon 0f in electrode h tions of the charge free from lenticular masses 0 lag the principle of the present invention. rig. d the prebaked segment; eing disposed op- 5 4 is a horizontal section throu h a furnace and pogitg the t l r masses. charge embodyint the principle of the invention.

It has now been found that the disadvantages PAUL LOUIS JosEPH MIGUET. described above ml! be avoided by providing an MARCH-l PAUL PERHDN. 

